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Toxicology Reports 2022Previous studies from our laboratory showed that prenatal exposure to hexavalent chromium, Cr(VI), caused premature ovarian failure and decreased pregnancy rates and...
Previous studies from our laboratory showed that prenatal exposure to hexavalent chromium, Cr(VI), caused premature ovarian failure and decreased pregnancy rates and litter size. Exposure to the endocrine disrupting chemicals (EDCs) can cause X-chromosome aneuploidy of the oocytes, increasing chromosome missegregation and risk of infertility, autoimmune diseases, cancers, and various genetic disorders. Cr(VI) is an EDC that is widely used in numerous industries. Environmental exposure to Cr(VI) caused detrimental reproductive effects in women and health effects in infants from California. Women with occupational Cr(VI) exposure experienced infertility, pregnancy loss, spontaneous abortion, and stillbirth. However, the adverse effects of Cr(VI) on oocyte development and quality have not been reported. Mitochondrial membrane potential and function are the critical determinants of oocyte quality in natural pregnancies and successful assisted reproductive techniques. The cytoskeletal machinery of the oocytes orchestrates the meiotic division of the oocytes, whereas cortical granules (CGs) prevent polyspermy. Therefore, the objective of the current study was to examine whether the mechanism by which Cr(VI) compromises oocyte quality and morphology is by altering cytoskeleton dynamics and mitochondrial function of the metaphase II (MII) oocytes. Rats were treated with environmentally relevant doses of Cr(VI) (1 and 5 ppm potassium dichromate) in drinking water from postnatal day (PND) 22-28, followed by superovulation and retrieval of MII oocytes. The data indicate that Cr(VI) exposure disrupted F-actin structure and distribution pattern, compromised mitochondrial function, altered CGs distribution, increased dysmorphic and degenerated oocytes, delayed first polar body extrusion, and caused infertility.
PubMed: 36518455
DOI: 10.1016/j.toxrep.2022.02.002 -
International Journal For Parasitology Aug 2021Molecular studies of gastrointestinal infections or microbiotas require either rapid sample processing or effective interim preservation. This is difficult in remote...
Molecular studies of gastrointestinal infections or microbiotas require either rapid sample processing or effective interim preservation. This is difficult in remote settings in low-income countries, where the majority of the global infectious disease burden exists. Processing or freezing of samples immediately upon collection is often not feasible and the cost of commercial preservatives is prohibitive. We compared fresh freezing (the 'gold standard' method), with low-cost chemical preservation in (i) a salt-based buffer consisting of DMSO, EDTA and NaCl (DESS) or (ii) 2.5% potassium dichromate (PD), for soil-transmitted helminth detection and microbiota characterisation in pre-school and school-aged children from north-western Thailand. Fresh frozen samples were frozen at -20°C on collection and maintained at -80°C within ~3 days of collection until molecular analysis, with international shipping on dry ice. In contrast, chemically preserved samples were collected and stored at ~4°C, transported on wet ice and only stored at -20°C on arrival in Australia ~8 weeks after collection, with international shipping on wet ice. DESS and PD provided better sensitivity for STH diagnosis, estimating higher infection rates (>80% for Ascaris lumbricoides and >60% for Trichuris trichiura; versus 56% and 15% for these parasites in fresh frozen samples) and egg abundance (inferred as gene copy number estimates). All methods performed similarly for microbiota preservation, showing no significant differences in alpha-diversity based on overall richness or inverted Simpson's Index. All three methods performed similarly for RNA and protein preservation in a small subset of samples. Overall, DESS provided the best performance, with the added benefit of being non-toxic, compared with PD, hence making it particularly applicable for studies in remote and resource-poor settings.
Topics: Animals; Child; Feces; Helminths; Humans; Microbiota; Soil; Trichuris
PubMed: 33774039
DOI: 10.1016/j.ijpara.2021.01.002 -
Acta Dermato-venereologica May 2015Atopic dermatitis is the most common chronic inflammatory disease among children in industrialised countries. Many factors influence this disease in a negative way and...
Atopic dermatitis is the most common chronic inflammatory disease among children in industrialised countries. Many factors influence this disease in a negative way and contact allergy is one such factor. The aim of the study was to examine the frequency of contact allergy among children with the diagnosis atopic dermatitis. Contact allergy was found in 22/82 children (26.8%), the most common from Amerchol L101 (11.0%), potassium dichromate (7.3%), and nickel sulfate (4.9%). A statistically significant difference in contact allergy frequency was demonstrated for those with hand and/or foot eczema compared to those without. Children with atopic dermatitis who suffer from hand and/or foot dermatitis should always be patch-tested to evaluate whether they have a relevant contact allergy and thus allergic contact dermatitis.
Topics: Adolescent; Age Distribution; Child; Child, Preschool; Cohort Studies; Comorbidity; Cross-Sectional Studies; Dermatitis, Allergic Contact; Dermatitis, Atopic; Female; Foot Dermatoses; Hand Dermatoses; Humans; Incidence; Male; Patch Tests; Prognosis; Retrospective Studies; Risk Assessment; Severity of Illness Index; Sex Distribution; Sweden
PubMed: 25367826
DOI: 10.2340/00015555-1995 -
Heliyon Jun 2021The activation of the Nrf2/HO-1 signaling pathway regulates cellular antioxidant stress and exerts anti-inflammatory and cytoprotective effects against acute lung injury...
The activation of the Nrf2/HO-1 signaling pathway regulates cellular antioxidant stress and exerts anti-inflammatory and cytoprotective effects against acute lung injury (ALI). The present study aimed to evaluate the therapeutic role of L-carnitine (LC) against potassium dichromate (PD) - induced acute lung injury in adult male albino rats via modulation of Nrf2/HO-1 signaling pathway. For this purpose, forty rats were randomly allocated into 5 groups (8 rats each). The normal group received intranasal (i.n.) saline, while the ALI group received intranasal instillation of PD as a single dose of 2 mg/kg. The 3d - 5th groups received PD then after 24 h administered L-carnitine (25, 50 and 100 mg/kg; orally) for 3 consecutive days. The therapeutic effect of L-carnitine was evaluated by assessment of serum levels of glutathione (GSH) and malondialdehyde (MDA) along with measurement of lung contents of transforming growth factor β1 (TGFβ1), protein kinase B (AKT), Nuclear factor erythroid-2 related factor 2 (Nrf2), Kelch-like ECH-associated protein 1 (Keap1), heme oxygenase-1 (HO-1), NAD(P)H quinone oxidoreductase 1 enzyme (NQO1) and glutathione cysteine ligase modifier subunit (GCLM) expression. Post-treatment with L-carnitine effectively increased the levels of GSH and AKT, elevated Nrf2 and its target genes and decreased the levels of MDA and TGFβ1 in comparison with PD control rats. Additionally, L-carnitine effectively reduced the number of goblet cell, inhibited the mucus formation in bronchioles and interstitial inflammatory infiltrate as well as alleviated the destruction of alveolar walls, and the congestion of blood vessels in lung tissue induced by PD. Our findings showed that L-carnitine may be a promising therapeutic agent against PD-induced acute lung injury.
PubMed: 34169163
DOI: 10.1016/j.heliyon.2021.e07207 -
Data in Brief Feb 2022The data were obtained by a label-free quantification approach from a shotgun proteomics experiment, using STrap sample processing technique for protein digestion and...
The data were obtained by a label-free quantification approach from a shotgun proteomics experiment, using STrap sample processing technique for protein digestion and high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS) for peptide analysis. MaxQuant data processing was used to obtain proteomics data. The dataset reflects changes in the liver protein profile of Japanese medaka exposed to 0, 5, 40 and 80 mg/L nominal concentrations of Sigma-Aldrich humic acid for 96 h. Actual concentrations of humic acid were measured using the potassium dichromate photometric method and reported in mg organic carbon/L. These proteomics data are relevant for further insights into fish stress responses to humic substances-related challenge.
PubMed: 35036493
DOI: 10.1016/j.dib.2022.107796 -
Journal of Parasitology Research 2020Bats are the only active flying placental mammals and are traditionally classified into mega- and microbats, which are, respectively, herbivorous and insectivorous in...
Bats are the only active flying placental mammals and are traditionally classified into mega- and microbats, which are, respectively, herbivorous and insectivorous in feeding habit. Though deforestation, habitat destruction, natural calamities, illegal hunting, and climate changes are the challenging threats for bats, the role of existing gastrointestinal (GI) parasites have not been evaluated yet in Nepal. Thus, the current study aims to determine the prevalence of GI parasites in bats from the Shaktikhor area at the Chitwan district of Southcentral Nepal. From July 2018 to February 2019, a total of 60 fecal samples of bats (30 from frugivorous bats and 30 from the insectivorous bats) were collected. These samples were preserved at 2.5% potassium dichromate solution. The fecal examination was carried out by the direct wet mount, concentrations, acid-fast staining, and sporulation techniques. Overall results showed the prevalence rate of 80% GI parasites. The parasites detected in the insectivorous bats were Ascarid spp., Capillarid sp., sp., spp., sp., sp., spp., sp., Oxyurid sp., Strongyle, and sp. In contrast, sp., sp., and sp. were detected in the frugivorous bats. Based on a wide diversity of parasite richness and parasitic concurrency measured by the prevalence rates, we suggest that GI parasitism might be a threatening factor in the insectivorous bats in the current study area.
PubMed: 33414955
DOI: 10.1155/2020/8880033 -
International Journal of Molecular... Jun 2023Environmental and occupational exposure to hexavalent chromium, Cr(VI), causes female reproductive failures and infertility. Cr(VI) is used in more than 50 industries...
Hexavalent Chromium Disrupts Oocyte Development in Rats by Elevating Oxidative Stress, DNA Double-Strand Breaks, Microtubule Disruption, and Aberrant Segregation of Chromosomes.
Environmental and occupational exposure to hexavalent chromium, Cr(VI), causes female reproductive failures and infertility. Cr(VI) is used in more than 50 industries and is a group A carcinogen, mutagenic and teratogenic, and a male and female reproductive toxicant. Our previous findings indicate that Cr(VI) causes follicular atresia, trophoblast cell apoptosis, and mitochondrial dysfunction in metaphase II (MII) oocytes. However, the integrated molecular mechanism of Cr(VI)-induced oocyte defects is not understood. The current study investigates the mechanism of Cr(VI) in causing meiotic disruption of MII oocytes, leading to oocyte incompetence in superovulated rats. Postnatal day (PND) 22 rats were treated with potassium dichromate (1 and 5 ppm) in drinking water from PND 22-29 and superovulated. MII oocytes were analyzed by immunofluorescence, and images were captured by confocal microscopy and quantified by Image-Pro Plus software, Version 10.0.5. Our data showed that Cr(VI) increased microtubule misalignment (~9 fold), led to missegregation of chromosomes and bulged and folded actin caps, increased oxidative DNA (~3 fold) and protein (~9-12 fold) damage, and increased DNA double-strand breaks (~5-10 fold) and DNA repair protein RAD51 (~3-6 fold). Cr(VI) also induced incomplete cytokinesis and delayed polar body extrusion. Our study indicates that exposure to environmentally relevant doses of Cr(VI) caused severe DNA damage, distorted oocyte cytoskeletal proteins, and caused oxidative DNA and protein damage, resulting in developmental arrest in MII oocytes.
Topics: Rats; Female; Animals; Male; Follicular Atresia; Chromium; Oxidative Stress; Oocytes; DNA Damage; Microtubules; Chromosomes
PubMed: 37373153
DOI: 10.3390/ijms241210003 -
Toxicology Research May 2018To explore the health effects of multi-heavy metal exposure, Sprague Dawley (SD) rats were orally given one dose of heavy metal mixtures (HMMs). The eight most common...
To explore the health effects of multi-heavy metal exposure, Sprague Dawley (SD) rats were orally given one dose of heavy metal mixtures (HMMs). The eight most common detectable heavy metals in Ningbo area are zinc (Zn), copper (Cu), manganese (Mn), chromium (Cr), nickel (Ni), cadmium (Cd), lead (Pb) and mercury (Hg). In this study, mixtures of these eight heavy metals were prepared using the compounds zinc sulfate heptahydrate, cupric sulfate, manganese dichloride, potassium dichromate, nickel dichloride, cadmium dichloride, lead acetate, and methyl mercury chloride with ion mass proportions of 1070.0, 312.6, 173.1, 82.6, 30.0, 13.3, 6.6, and 1.0, respectively. The rats were randomly divided into four groups. Beside the control group, each rat received a corresponding dose of HMMs 215, 464 or 1000 mg per kg body weight (bwt), respectively. The rats were observed for 4 weeks. During the last week of observation, the Morris water maze test was used to investigate spatial learning and memory in the treated rats. The rats were exsanguinated under complete chloral hydrate anesthesia and organ coefficients were measured. Biochemical tests of blood and serum samples were carried out. The results showed abnormalities in the hematological system, decreased renal function, hepatic injury and disturbances in the electrolyte balance of the rats treated with a high dose of HMMs. Death of some rats was also observed. This paper analyzed how a one-time high dose oral administration of HMMs induced systemic toxicity.
PubMed: 30090589
DOI: 10.1039/c7tx00260b -
Actas Dermo-sifiliograficas 2017Few epidemiological studies have investigated the incidence of allergic contact dermatitis in children. Underdiagnosis has been observed in some studies, with many cases...
BACKGROUND
Few epidemiological studies have investigated the incidence of allergic contact dermatitis in children. Underdiagnosis has been observed in some studies, with many cases in which the condition is not suspected clinically and patch tests are not performed. However, the prevalence of pediatric sensitization to allergens has been reported to be as high as 20%, and the diagnosis should therefore be contemplated as a possibility in this age group.
MATERIAL AND METHODS
We performed a retrospective analysis of the skin allergy database of the Dermatology Department of Consorcio Hospital General Universitario de Valencia. Children between 0 and 16 years of age diagnosed with allergic contact dermatitis in the previous 15 years (between 2000 and 2015) were included in the analysis. Epidemiological (age, sex, history of atopy) and clinical (site of the lesions, allergen series applied, positive reactions, and their relevance) variables were gathered.
RESULTS
Patch tests had been performed on 4,593 patients during the study period. Of these, 265 (6%) were children aged between 0 and 16 years. A positive reaction to at least one of the allergens tested was observed in 144 (54.3%) patients in that group. The allergens most frequently identified were the following (in decreasing order of frequency): thiomersal, cobalt chloride, colophony, paraphenylenediamine, potassium dichromate, mercury, and nickel. The sensitization was considered relevant in 177 (61.3%) cases.
CONCLUSIONS
More than half of the children studied showed sensitization to 1 or more allergens, with a high percentage of relevant sensitizations. All children with a clinical suspicion of allergic contact dermatitis should be referred for patch testing. As no standardized test series have been developed for this age group, a high level of clinical suspicion and knowledge of the allergens most commonly involved are required when selecting the allergens to be tested.
Topics: Adolescent; Allergens; Child; Child, Preschool; Databases, Factual; Dermatitis, Allergic Contact; Drug Hypersensitivity; Female; Humans; Hypersensitivity, Immediate; Infant; Infant, Newborn; Male; Patch Tests; Prevalence; Retrospective Studies; Spain; Tertiary Care Centers
PubMed: 28284423
DOI: 10.1016/j.ad.2016.12.018 -
Food Chemistry: X Mar 2022Effect of tea pruning litter biochar (TPLBC) on arsenic (As), cadmium (Cd) and chromium (Cr) content in made tea and successive tea infusions were investigated in a...
Effect of tea pruning litter biochar (TPLBC) on arsenic (As), cadmium (Cd) and chromium (Cr) content in made tea and successive tea infusions were investigated in a greenhouse experiment with two tea cultivars (TV23 and S.3A/3). Made tea prepared from TV23 and S.3A/3 clone, a decrease in the concentration of As, Cd, and Cr by 36.73%, 16.22%, 13.96%, and 36.63%, 27.78%, 10.54%, respectively over control on the application of the highest dose of TPLBC (500 kg TPLBC ha). Irrespective of treatments, studied element concentrations were significantly higher (p ≤ 0.05) in the first infusion and lower in the third. Considering Ten g made tea consumption per person per day, the maximum average daily intakes of As, Cd and Cr in a higher dose of TPLBC were far below the tolerable weekly intake prescribed by the World Health Organization. As hazard quotient values of selected elements were ≪ 1, no significant adverse health consequences are expected for tea consumers.
PubMed: 35498976
DOI: 10.1016/j.fochx.2022.100255